|Appearance||Period 36: The Fish Family|
Disappointed that her family is unable to go on vacation like her friends, Rie attempts to focus on making herself comfortable and incidentally neglects one of the families fish.
Rie is a thin, young girl with big rounded eyes and short hair worn in pigtails at her ears. Her bangs are straight cut and her forelocks are ear length.
With it being summer and warm, she is mainly shown wearing tank-tops and shorts with colorful patterns.
Childish and somewhat thoughtless, Rie struggles to prioritize and take care of responsibilities. She doesn't care for the family fish at first but was very guilty after accidentally letting one die. She is also shown to be fairly lazy and bickers with her mom over the decisions she makes. However, she adores her parents and is shown to get along with them.
One day, Rie had been enviously talking to her friend who had been preparing on leaving during summer break. She attempted to ask her mother if they could go on a vacation or visit somewhere fun too, but her mother refused. On her way out, she kept reminding Rie to feed the fish with care; which Rie found to be unfair as she didn't even want them to begin with. Frustrated over the discussion she dumps in a bunch of food and remembers a project she had to work on- but not wanting to actually do any work, she decides to draw a picture of a fish instead.
She scoops one out of the tank to observe it while she draws, but before she could get it a water-filled cup the fish flopped to the ground. Confused, she poked and prodded the fish until an anime she likes came on, distracting her until the program ended, when she decided to grab some ice cream. In this time she remembers the poor fish on the floor, and in a hurry to discard it when her mother gets home she tosses it into the trash. Her mother asks if she remembered to feed them as she asked, and shaken by what happened, Rie claims she did.
Over the course of the evening, Rie was haunted by what she had accidentally done, and she found herself growing concerned when the grilled salmon her mother served appeared to be looking at her. She went on to have a horrible nightmare involving the fish surrounding her, and the following morning began to see her parents transform into fish before realizing she had scales on her body.
Horrified, Rie attempted to dig through the trash in hopes of burying the fish thinking they would forgive her. But when she couldn't find it, she turned to the tank after seeing how monstrous her parents looked by this point and begged the fish to return them to normal, offering to let them do anything to her in return.
Suddenly, Rie finds herself with her parents, now back to normal worriedly observing her. Her mother confessed that she had been concerned over Rie and found out about the fish, but if she had known how horrible she was feeling she would have brought it up with her instead of waiting for her to confess to it. She comforts her daughter by showing the fish had been given a burial, and inspired by this nightmare; Rie decides to show the fish the true attention they deserve. However, she did not hear the news program and is unaware that everyone will have to have surgery for gills when they turn ten and fails to see that her parents already have them.
With Rie being that age, Yomi announces that she will need to get it soon.
- Rie is one of the only characters with a known age.
- On the credits page of the her chapter, an eaten fish with Rie's hair is depicted.
- She physically resembles Miya Maeshima.